Structural corner

ABSTRACT

A corner frame construction in which three angle members, each having an identical end configuration, are joined in interlocking relation at their ends to form a corner having a smooth and rigid external surface.

PATENIEu m 3586.359

- sum 1 or 2 INVISN'IUA.

Edward P Cecelsk/ Y ATTORNEY United States Patent Edward Peter Cecelski Freehold, NJ. 879,688

Nov. 25, 1969 June 22, 1971 RCA Corporation Inventor Appl No. Filed Patented Assignce STRUCTURAL CORNER 11 Claims, 4 Drawing Figs.

US. Cl 287/l89.36B, 287/54 A. 287/1 89.36 H 1nt.C1 Fl6b 7/00 Field of Search 287/1 89.36 R, 189.36 C, 189.36 D, 54 A, 54 B, 54 C, 189.36

F, 189.36 H, 20.92 R, 20.92 C, 20.92 D, 20.92 DB, 189.36 B;2l 1/177, 178, 182, 183; 52/280, 656

References Cited UNITED STATES PATENTS 1/1889 Linderman 287/20.92 D X 4/1916 Niernsee 287/54 B X 7/1952 Holmes 287/54 C UX 9/1952 Hanesse 287/189.36 X 8/1966 'Durnbaugh et a1. 287/189.36H 2/1967 Henderson 287/l89.36 H

Primary ExaminerDavid J. Williamowsky Assistant Examiner--Wayne L. Shedd AuomeyEdward J. Norton ABSTRACT: A corner frame construction in which three angle members, each having an identical end configuration, are joined in interlocking relation at their ends to form a corner having a smooth and rigid external surface.

PATENTED JUH22 |97l SHEET 2 OF 2 INVliN'IUK Edward P. Cecels-lr/f WQ )1 ATTORNEY STRUCTURAL CORNER Generally, frameworks for electrical apparatus are made of angle members which are joined at the ends thereof to form structural corners. The configuration of the angle members is such that the comers need special consideration in order to provide structural and aesthetic qualities to a frame. Usually the angles are welded, bolted or otherwise joined in end to end relation. If welded, the welds need to be ground down or otherwise finished to provide a smooth appearance. If bolted together, which is less common than welding, then the angles may be bent to form a corner, in which structural rigidity and a clean smooth appearance may be sacrificed.

A condition common to the prior art structures is that large frameworks have a tendency to bend in parallax, that is, the frames have a tendency to warp out of their desired configuration. This condition is attributed to weakness of the corner structure. To counteract this weakness, corners have been developed which are costly and complex.

It is an object of the present invention to provide a structural framework corner that is mechanically sound and strong and which is simple, reliable and inexpensive to construct.

It is another object to provide a structural framework comer that is formed by the interlocking of three angle members in such a manner as to provide a rigid structural corner that has smooth external surfaces.

As herein described, a comer frame construction is provided in which three members are each interlocked at one end thereof to form a trihedral corner. Each member includes an angle bar comprising a first leg having a transverse edge and a longitudinal edge intersecting at one end thereof and a second leg depending from the first leg at the longitudinal edge in a given direction. The legs terminate adjacent the one end such that the first leg extends beyond the termination of the second leg a predetermined distance. A tab depends in the given direction a given length from the first leg at the transverse edge. The predetermined distance is smaller than the given length and greater than the width of the tab.

In the drawing:

FIG. 1 is a perspective view of one member embodying the invention.

FIG. 2 is an exploded view in perspective of a structural comer utilizing the member illustrated in FIG. ll.

FIG. 3 is a perspective interior view of the assembled corner including three members of the type shown in FIG. 1.

FIG. 4 is an exterior perspective view of the assembled comer of FIG. 3.

A comer structure embodying the invention preferably includes identical end configurations on three angle members such as end 100 of structural angle member 25, shown in FIG. I. The other end of each of'the members, not shown, may also include this configuration. These angle members may each be made from identical stock comprising two longitudinally extending legs L1 and L2, which may be of equal width.

The angle members may comprise sheet material, or a drawn material such as aluminum of suitable thickness. The thickness and width of the legs may be of any suitable dimension.

Angle member may be fabricated from a drawn angle member made of aluminum having a first leg L1 and a second leg L2 depending therefrom in direction x at longitudinal edge 60, the legs L1 and L2 preferably being joined at right angles. Leg L2 terminates at edge 65 perpendicular to leg Ll. Leg Ll terminates at transverse edge 70, which edge intersects and is perpendicular to longitudinal edge 60. Edge 65 is disposed perpendicular to and intersecting longitudinal edge 60 distance B from transverse edge 70 of leg Ll. A continuation of transverse edge 70 forms the line of intersection of interior surface 71 of tab T1 and interior surface 31 of leg L1.

Tab T1 is the extended end of leg L1 bent perpendicular thereto in the general direction of arrow x, in which direction tab T1 has a length C. Edge 80 of tab T1 is offset from edge 60 at location 64 a distance A along edge 70 perpendicular to edge 60. Offset distance A is greater than twice the thickness of the material of leg L1 at end 100, the thickness of both legs L1 and L2 at end 100 being substantially the same. Distance A preferably is that dimension which will permit two thicknesses of material at end 100 to be closely disposed between edge 60 and edge parallel to edge 60 and edge 80. Edge 81 of tab T1 is coextensive with longitudinal edge 61 of leg Ll. Tab T1 is an extension of leg L1 from which a rectangular section of 7 material defined by edge 80 and edge 70 at location 64 was removed. Similarly, a rectangular section of material has removed from leg L2 at edge 65 a distance equal to B plus C.

The internal bend radius 102 at edge 70 between tab T1 and leg L1 is preferably smaller than the external radius of corner 5 of tab Tl. These radii optimize the abutting interlocking arrangement of the members. The width W and length C of tab T1 are related to predetermined distance B such that distance B is greater than width W and smaller than distance C. This relationship permits three members having ends identical to end to be interlocked to form a trihedral corner. The bend of tab T1 and the cutouts from member 25 may be made by any suitable tool.

Exterior surface 41 of leg L2 is coextensive with edge 60 forming a smooth continuous surface therewith. Interior surface 71 of tab TI is coplanar with transverse edge 70. However, exterior surface 73 of tab T1 may also be coplanar with edge 70. In the former instance where surface 71 is coplanar with edge 70, this configuration simplifies the bending of tab T1 sharply at edge 70. Edge 70, being offset from the exterior surface 73 of tab T1, leaves a slight recess at area 64. The effect of this recess is shown by the corner of FIG. 4 wherein the external corner surface has a cavity 1. This cavity can be reduced in size by fabricating the surface 73 of tab T1 coplanar with edge 70. In either case, the cavity 1 has a maximum dimension equal to the offset distance A, which may be made relatively small as compared to the width W, according to the dimensions of the angle members employed.

The three angle members 25, 26 and 27 of FIG. 2 each have an end identical with the end 100 configuration of angle member 25 of FIG. I, and may be assembled in interlocking relationship to form a structural corner with smooth external surfaces as shown by the corner of FIG. 4. In assembling the angle members to form the corner of FIG. 2, angle member 25 is transposed in the direction of arrow 97 and member 26 is transposed in direction of arrow 98 until tab T1 overlaps leg L1 of member 26 and tab T2 overlaps leg L2 of member 25. Tab TI is juxtaposed with leg Ll of member 26 in interior area 31, while tab T 2 is juxtaposed with leg L2 of member 25 in area 42. Tab T1 is disposed intermediate and perpendicular to tab T2 and leg L2 at edge 65 of member 26, and parallel to leg L1 of member 26 adjacent interior surface 31.

Transverse edge 70 of member 25 is parallel to and adjacent longitudinal edge 60 of member 26. Offset edge 80 of member 25 is parallel to and adjacent transverse edge 70 of member 26. Leg Ll of member 25 and leg L2 of member 26 are disposed coplanar such that their edges 61 and 65, respectively, abut. Width W of tab Tl (FIG. 1) is dimensioned such that this tab is closely received intermediate the terminated edge 65 of leg L2 and interior surface 71 of tab T2 of member 26, the width W being less than distance B.

Tab T2 having a length C (FIG. 1) in given direction x, which is greater than distance B, for example, twice distance B, overlaps and is juxtaposed with leg L2 in interior area 42 of member 25. Thus, leg L2 of member 25 is externally displaced with respect to tab T2 of member 26. Similarly, tab T1 is displaced interior to leg L1 of member 26 at area 31 thereof.

Once having assembled members 25 and 26 in this relationship, there exists between offset edge 80 0f member 26 and edge 60 of member 25 a gap having a width greater than the thickness of tab T3 of member 27, the thickness of all the tabs being substantially the same.

When leg L2 of member 26 is parallel and coplanar with leg Ll of member 25, edge 80 of tab T2 is displaced from the extended interior surface 42 of leg L2 of member 26 a distance greater than the thickness of the material, which distance is the gap indicated. Tab T3 of member 27 is inserted into this gap in direction of arrow 99 intermediate tab TI and edge 65 of member 25. Tab T3 is parallel to leg L1 of member 25 and leg L2 of member 26, and is juxtaposed with member 26 at area 42 and member 25 at area 31. By transposing each respective member in a different one of the directions of arrows 97 98 and 99, each of the tabs are adjacent to and in juxtaposition with the coplanar legs L] and L2. Once assembled, any two members have the identical relationship as that described for members 25 and 26.

Tabs T1, T2 and T3, once disposed in their interlocked relation, form an interior corner as shown in FIG. 3. Tab T2 is intermediate tab T3 and leg L2 of member 27 at edge 65. Tab T3, similarly, is intermediate tab TI and edge 65 of member 25 as is tab T1 with respect to tab T2 and edge 65 of member 26. In each of the members, offset edge 80 is parallel and adjacent to edge 70 (FIG. 2) of a second member. Further, each of legs Ll are coplanar with legs L2 of another member, and each tab is in juxtaposition with a leg Ll of one other member and leg L2 of a second other member.

In the assembled condition, each of the legs LI at edge 61 (FIG. 2) abuts with leg L2 of an adjacent member at edge 65 and are coplanar therewith as described. Thus, in the external view as shown by FIG. 4, the joined members present a smooth external surface.

In FIG. 2, edge 80 abuts edge 70 of a next adjacent member; to permit uniform interlocking relationship of all the members, edge 80 should abut uniformly adjacent to interior surface 71 of the next adjacent tab. Thus, exterior surface 73 of each of the tabs will contact the areas 31 and 42 of Legs LI and L2, providing a smooth exterior surface. This is shown by FIG. 4 in which coextensive surface 41 of one member is coplanar with surface 49 of another member. In this instance, edge 80 abuts interior tab surface 71 which provides additional strength to the corner. Of course, if edge 80 is offset a distance substantially greater than twice the thickness, for example, three times the thickness, then the abutting relation is no longer present between edge 80 and surface 71.

A three dimensional frame structure may be readily assembled with the corner structure of the present invention, since any two members may be joined prior tothe assembly of the third member. Any two joined members have the identical relationships with respect to each other at the one end thereof regardless of which two of the three members are assembled first. The use of an adhesive intermediate the tabs and juxtaposed legs, welding or other fastening means is dependent on the particular application.

Each of the members, regardless oflength, may have identical ends, thus increasing the fabrication cost saving. The use of members having identical interlocking ends provides the strength, aesthetic quality, and low cost not available in other constructions. Although a particular embodiment of the invention has been shown and described, changes or modifications will readily suggest themselves. In particular,the members need not be right angle members, nor need they be joined to each other to form a right trihedral corner, as other angular relationships between the members could alternatively be employed. In some instances, the members need not have identical end configurations in order to be interlocked in the manner described;

According to the arrangement of FIG. 2, each member may be fastened by means not shown to both of the other members; further, the fastening means for any one member may join that member in each of the three planes which comprise the comer. In addition, the abutting and interlocked relationship enhances the strength of the comer by limiting the possible motion of any member to a direction opposite to directions 97, 98 or 99, which motions are prevented by the fastening means. In a parallax bending condition of a frame construction, at least one of the members bends generally in one of the directions 97, 98 or 99. With the present invention, abutting edges 61 and 65 prevent this condition.

What I claim is:

I. A member for use in a corner frame construction in which three members are each interlocked at one end thereof to form a trihedral corner, said member comprising:

an angle bar comprising a first leg having a transverse edge and a longitudinal edge intersecting at said end, and a second leg depending from said first leg at said longitudinal edge in a given direction, said leg terminating adjacent said end such that said first leg extends beyond the termination of said second leg a predetermined distance, and

a tab depending in said given direction a given length from said first leg at said transverse edge,

said predetermined distance being smaller than said given length and greater than the width of said tab.

2. The member of claim 1, wherein said first and second legs and said tab are mutually orthogonal to one another.

3. The member of claim 1, wherein said legs and said tab are made of material having substantially the same thickness adjacent said end.

4. The member of claim 3, wherein the width of said first leg along said transverse edge is at least equal to said predetermined distance plus twice said thickness, said second leg having one surface thereof coextensive with said longitudinal edge, and a second surface oppositely disposed said one surface intersecting said first leg a distance from said longitudinal edge substantially equal to said thickness,

said tab having one surface thereof coextensive with said transverse edge, and an edge thereof intersecting said transverse edge offset a predetermined distance from said longitudinal edge.

5. The member of claim 4, wherein said offset distance is greater than twice said thickness.

6. A corner frame construction in which three members are each interlocked at one end thereof to form a trihedral corner, each member comprising:

a right angle bar made of substantially rigid material having uniform thickness comprising a first leg having a transverse and a longitudinal edge intersecting at said end, and a second leg depending from said first leg at said longitudinal edge in a given direction, said legs terminating adjacent said end such that said first leg extends beyond the termination of said second leg a predetermined distance, and

a tab depending in said given direction a given length from said first leg at said transverse edge perpendicular to said first and second legs, said tab having first and second longitudinal edges,

said predetermined distance being smaller than said given length and greater than the width of said tab,

said first longitudinal edge intersecting said transverse edge a distance offset from said angle bar longitudinal edge at least twice said thickness, and said second tab longitudinal edge intersecting said transverse edge a distance from said angle bar longitudinal edge a distance not greater than said first leg width.

7. A corner frame construction in which three members are each interlocked at one end thereof to form a trihedral corner, comprising:

three angle members of sheet material of uniform thickness at said one end disposed in angular relationship,

each of said angle members comprising a first leg having a transverse and a longitudinal edge intersecting at said end and a second leg depending from said first leg at said longitudinal edge in a given direction, said legs terminating adjacent said end, an end portion of said first leg being extended beyond the termination of said first leg a predetermine distance to said transverse edge,

a tab depending a given length from said transverse edge in said given direction,

an edge of said tab intersecting said transverse edge a distance offset from said longitudinal edge an amount at least equal to twice said thickness, said predetermined distance being'smaller than said given length and greater than the width of said tab,

said three angle members being assembled to provide a smooth comer structure with each first leg of any one member being coplanar with the second leg of another one of said three members, the tab of said one member being disposed parallel to the first leg of said other member in juxtaposition therewith intermediate the tab and the terminated end of the second leg of said other member, the tab of the other member being disposed parallel to and in juxtaposition with the second leg of the one member, the offset edge of the one member and the transverse edge of the other member being adjacent and parallel to each other, said tabs of all said members forming an inner corner in juxtaposition with the corner formed by said first and second legs of said three members.

8. The frame of claim 7, further including means for joining each of the tabs to at least one of the legs which are in juxtaposition therewith.

9. The frame of claim 8, wherein said joining means includes at least one weld.

10, A corner frame construction in which three members are each interlocked at one end thereof to form a trihedral comer, comprising:

three right angle members of sheet material of uniform thickness at said one end disposed in mutual perpendicular relationship,

each of said angle members comprising a first leg having a transverse and longitudinal edge intersecting at right angles at said end and a second leg depending mutually perpendicularly from said first leg at said longitudinal edge in a given direction, said legs terminating adjacent said end,

an end portion of said first leg being extended beyond the termination of said first leg a predetermined distance to said transverse edge,

a tab mutually perpendicular to said first and second legs extending from said transverse edge a given length in said given direction,

an edge of said tab intersecting said transverse edge a distance offset from said longitudinal edge an amount at least equal to twice said thickness, said predetermined distance being smaller than said given length and greater than the width of said tab,

said three angle members being assembled to provide a smooth corner structure with each first leg of any one member being coplanar with the second leg of another one of said three members, the tab of said one member being disposed parallel to the first leg of said other member in juxtaposition therewith intermediate the tab and the terminated end of the second leg of said other member, the tab of the other member being disposed parallel to and in juxtaposition with the second leg of the one member, the offset edge of the one member and the transverse edge of the other member being adjacent and parallel to each other, said tabs of all said members forming an inner corner in juxtaposition with the corner formed by said first and second legs of said three members.

11. The frame of claim 10, further including means forjoining each of the tabs of one member to at least one of the legs of the other members which are in juxtaposition therewith. 

1. A member for use in a corner frame construction in which three members are each interlocked at one end thereof to form a trihedral corner, said member comprising: an angle bar comprising a first leg having a transverse edge and a longitudinal edge intersecting at said end, and a second leg depending from said first leg at said longitudinal edge in a given direction, said leg terminating adjacent said end such that said first leg extends beyond the termination of said second leg a predetermined distance, and a tab depending in said given direction a given length from said first leg at said transverse edge, said predetermined distance being smaller than said given length and greater than the width of said tab.
 2. The member of claim 1, wherein said first and second legs and said tab are mutually orthogonal to one another.
 3. The member of claim 1, wherein said legs and said tab are made of material having substantially the same thickness adjacent said end.
 4. The member of claim 3, wherein the width of said first leg along said transverse edge is at least equal to said predetermined distance plus twice said thickness, said second leg having one surface thereof coextensive with said longitudinal edge, and a second surface oppositely disposed said one surface intersecting said first leg a distance from said longitudinal edge substantially equal to said thickness, said tab having one surface thereof coextensive with said transverse edge, and an edge thereof intersecting said transverse edge offset a predetermined distance from said longitudinal edge.
 5. The member of claim 4, wherein said offset distance is greater than twice said thickness.
 6. A corner frame construction in which three members are each interlocked at one end thereof to form a trihedral corner, each member comprising: a right angle bar made of substantially rigid material having uniform thickness comprising a first leg having a transverse and a longitudinal edge intersecting at said end, and a second leg depending from said first leg at said longitudinal edge in a given direction, said legs terminating adjacent said end such That said first leg extends beyond the termination of said second leg a predetermined distance, and a tab depending in said given direction a given length from said first leg at said transverse edge perpendicular to said first and second legs, said tab having first and second longitudinal edges, said predetermined distance being smaller than said given length and greater than the width of said tab, said first longitudinal edge intersecting said transverse edge a distance offset from said angle bar longitudinal edge at least twice said thickness, and said second tab longitudinal edge intersecting said transverse edge a distance from said angle bar longitudinal edge a distance not greater than said first leg width.
 7. A corner frame construction in which three members are each interlocked at one end thereof to form a trihedral corner, comprising: three angle members of sheet material of uniform thickness at said one end disposed in angular relationship, each of said angle members comprising a first leg having a transverse and a longitudinal edge intersecting at said end and a second leg depending from said first leg at said longitudinal edge in a given direction, said legs terminating adjacent said end, an end portion of said first leg being extended beyond the termination of said first leg a predetermine distance to said transverse edge, a tab depending a given length from said transverse edge in said given direction, an edge of said tab intersecting said transverse edge a distance offset from said longitudinal edge an amount at least equal to twice said thickness, said predetermined distance being smaller than said given length and greater than the width of said tab, said three angle members being assembled to provide a smooth corner structure with each first leg of any one member being coplanar with the second leg of another one of said three members, the tab of said one member being disposed parallel to the first leg of said other member in juxtaposition therewith intermediate the tab and the terminated end of the second leg of said other member, the tab of the other member being disposed parallel to and in juxtaposition with the second leg of the one member, the offset edge of the one member and the transverse edge of the other member being adjacent and parallel to each other, said tabs of all said members forming an inner corner in juxtaposition with the corner formed by said first and second legs of said three members.
 8. The frame of claim 7, further including means for joining each of the tabs to at least one of the legs which are in juxtaposition therewith.
 9. The frame of claim 8, wherein said joining means includes at least one weld.
 10. A corner frame construction in which three members are each interlocked at one end thereof to form a trihedral corner, comprising: three right angle members of sheet material of uniform thickness at said one end disposed in mutual perpendicular relationship, each of said angle members comprising a first leg having a transverse and longitudinal edge intersecting at right angles at said end and a second leg depending mutually perpendicularly from said first leg at said longitudinal edge in a given direction, said legs terminating adjacent said end, an end portion of said first leg being extended beyond the termination of said first leg a predetermined distance to said transverse edge, a tab mutually perpendicular to said first and second legs extending from said transverse edge a given length in said given direction, an edge of said tab intersecting said transverse edge a distance offset from said longitudinal edge an amount at least equal to twice said thickness, said predetermined distance being smaller than said given length and greater than the width of said tab, said three angle members being assembled to provide a smooth corner structure with each first leg of any one member being coplanar with the second leg of another one of said three members, the tab of said one member being disposed parallel to the first leg of said other member in juxtaposition therewith intermediate the tab and the terminated end of the second leg of said other member, the tab of the other member being disposed parallel to and in juxtaposition with the second leg of the one member, the offset edge of the one member and the transverse edge of the other member being adjacent and parallel to each other, said tabs of all said members forming an inner corner in juxtaposition with the corner formed by said first and second legs of said three members.
 11. The frame of claim 10, further including means for joining each of the tabs of one member to at least one of the legs of the other members which are in juxtaposition therewith. 